to_text_xml(mod): include the XML declaration with the encoding of the content

src/encoding_type.rs

@@ -62,6 +62,17 @@ impl EncodingType {
     }
   }
 
+  pub fn name(&self) -> Option<&'static str> {
+    match *self {
+      EncodingType::None       => None,
+      EncodingType::ASCII      => None,
+      EncodingType::ISO_8859_1 => Some(WINDOWS_1252.name()),
+      EncodingType::EUC_JP     => Some(EUC_JP.name()),
+      EncodingType::SHIFT_JIS  => Some(SHIFT_JIS.name()),
+      EncodingType::UTF_8      => Some(UTF_8.name()),
+    }
+  }
+
   fn decode_ascii(input: &[u8]) -> Result<String, KbinError> {
     // ASCII only goes up to 0x7F
     match input.iter().position(|&ch| ch >= 0x80) {

src/to_text_xml/mod.rs

@@ -1,13 +1,16 @@
 use std::io::{Cursor, Write};
 
 use quick_xml::Writer;
+use quick_xml::events::{BytesDecl, Event};
 
+use encoding_type::EncodingType;
 use error::KbinError;
 
 mod node;
 mod node_collection;
 
 pub trait ToTextXml {
+  fn encoding(&self) -> EncodingType;
   fn write<W: Write>(&self, writer: &mut Writer<W>) -> Result<(), KbinError>;
 }
 
@@ -28,6 +31,12 @@ impl TextXmlWriter {
   pub fn to_text_xml<T>(mut self, value: &T) -> Result<Vec<u8>, KbinError>
     where T: ToTextXml
   {
+    if let Some(encoding) = value.encoding().name() {
+      let header = BytesDecl::new(b"1.0", Some(encoding.as_bytes()), None);
+
+      self.xml_writer.write_event(Event::Decl(header))?;
+    }
+
     value.write(&mut self.xml_writer)?;
 
     Ok(self.xml_writer.into_inner().into_inner())

src/to_text_xml/node.rs

@@ -5,6 +5,7 @@ use quick_xml::Writer;
 use quick_xml::events::{BytesEnd, BytesStart, BytesText, Event};
 use quick_xml::events::attributes::Attribute;
 
+use encoding_type::EncodingType;
 use error::KbinError;
 use node::Node;
 use node_types::StandardType;
@@ -12,6 +13,11 @@ use to_text_xml::ToTextXml;
 use value::Value;
 
 impl ToTextXml for Node {
+  /// At the moment, a `Node` will always contain UTF-8 data.
+  fn encoding(&self) -> EncodingType {
+    EncodingType::UTF_8
+  }
+
   fn write<W: Write>(&self, writer: &mut Writer<W>) -> Result<(), KbinError> {
     let key = self.key();
     let mut elem = BytesStart::borrowed(key.as_bytes(), key.as_bytes().len());

src/to_text_xml/node_collection.rs

@@ -5,12 +5,19 @@ use quick_xml::Writer;
 use quick_xml::events::{BytesEnd, BytesStart, BytesText, Event};
 use quick_xml::events::attributes::Attribute;
 
+use encoding_type::EncodingType;
 use error::{KbinError, KbinErrorKind};
 use node::NodeCollection;
 use node_types::StandardType;
 use to_text_xml::ToTextXml;
 
 impl ToTextXml for NodeCollection {
+  /// At the moment, decoding the value of a `NodeDefinition` will decode
+  /// strings into UTF-8.
+  fn encoding(&self) -> EncodingType {
+    EncodingType::UTF_8
+  }
+
   fn write<W: Write>(&self, writer: &mut Writer<W>) -> Result<(), KbinError> {
     let base = self.base();
     let key = base.key()?.ok_or(KbinErrorKind::InvalidState)?;